Current and future public health is characterized by the increase of chronic and degenerative diseases, corresponding to the worldwide ageing of the population. The increasing prevalence of these conditions together with the long incubation period of the chronic diseases and the continual technological innovations, offer new opportunities to develop strategies for early diagnosis.
Public Health has an important mandate to critically assess the promises and the pitfalls of disease screening strategies. This MOOC will help you understand important concepts for screening programs that will be explored through a series of examples that are the most relevant to public health today. We will conclude with expert interviews that explore future topics that will be important for screening.
By the end of this MOOC, students should have the competency needed to be involved in the scientific field of screening, and understand the public health perspective in screening programs.
This MOOC has been designed by the University of Geneva and the University of Lausanne.
This MOOC has been prepared under the auspices of the Ecole romande de santé publique (www.ersp.ch) by Prof. Fred Paccaud, MD, MSc, Head of the Institute of Social and Preventive Medicine in Lausanne (www.iumsp.ch), in collaboration with Professor Antoine Flahault, MD, PhD, head of the Institute of Global Health, Geneva (https://www.unige.ch/medecine/isg/en/) and Prof. Gillian Bartlett-Esquilant (McGill University, Quebec/ Institute of Social and Preventive Medicine, Lausanne).

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Cancer Screening

Cancer is a classical field for screening because of both the improvement of the prognosis for most cancers and the usually long incubation period. This part of the MOOC will present current data, evidence and policies regarding the most important cancer sites that include colorectum, prostate, lung, cervix, breast and skin. This module is given by several experts including Elisabetta Rapiti from the Geneva Cancer Registry at the Institute of Global Health in Geneva; Professor Antoine Flahault, who is the Head of the Institute of Global Health in Geneva; and Jean-Luc Buillard who is a Senior Lecturer in the Division of Chronic Diseases at the Institute for Social and Preventive Medicine in Lausanne. A quiz will complete this module.

Conheça os instrutores

Antoine Flahault

Professor of Public Health and Director of the Institute of Global Health (Faculty of Medicine, University of Geneva) and co-Director of Centre Virchow-Villermé (Université Paris Descartes)University of Geneva and Université Paris Descartes – Sorbonne Paris Cité

Fred Paccaud (In Partnership with UNIGE)

Professor of epidemiology and public health and Director of the Institute of social and preventive medicineLausanne University Hospital

Gillian Bartlett-Esquilant

Professor of Epidemiology and Research and Graduate Program Director and Associate Chair for the Department of Family Medicine at McGill University.University of Lausannne and McGill University

[MUSIC]

Yes, good morning.

So the question is about lung cancer.

Is it possible to envisage any early detection of lung cancer?

The problem of lung cancer is it is one of the cancer which

is really associated with a high level of mortality.

Survival after diagnosis of lung cancer is very catastrophic.

It has not evolved since after civil war.

Well, one or two.

Meaning that, in fact, most of the cancer have benefited from tremendous,

dramatic increase of survival due to, of course, early diagnosis.

But also, of course, of new chemotherapy, and radiation,

and all the treatment of cancer, but not for the lung cancer.

One of the reason is lung cancer is very deep inside the body and

very hard to detect.

And particularly hard to detect early.

When you detect it, it's because sometimes you are coughing blood.

And because of that, that means that the cancer is already very developed.

It's not an early phase of the cancer when you detect it.

So because of that and because of the prognosis of lung cancer,

it was stuck with no real progress since after the World War Two.

So what happened is because of the new imaging, because standard chest X-ray,

the standard radiography of thorax cannot help you so much.

Because when you detect an image,

an anomaly on the chest X-rays, it means it is too big.

You can't detect the very, very small tumors.

But thanks to the CT scan it has been possible to envisage

a detection of very, very small tumor and maybe at early stage.

And when you see that because of the stage you may have a better survival

when it is early.

The small tumor, the early phase,

early stage tumor may be associated with much better prognosis.

And you can detect them through the low dose CT scan.

It may happen that because of that,

because of that new technology you may save lives.

That was a question.

And it takes time to demonstrate that.

First of all, there was a very big study which is named ELCAP for

Early Lung Cancer Action Program.

It was an open study where all the patients, not the patients, smokers,

in fact.

They were not patients, they did not had any symptoms.

And they come to the physicians for a CT scan, a low dose CT scan.

And it has been recorded and their survivals have been recorded.

And it has demonstrated much better survival than what was expected

just because of the long time service we had and the experience of lung cancer.

It was published in the New England Journal of Medicine.

And the leader of this program, Claudia Henschke from

New York City said « no, the game is over.

You should screen all the smokers for

this early diagnosis of lung cancer.

And if you detect one, you have now to go to the surgery and

to really extract the tumor and you can cure your patient. »

But there was bruise, I would say, and there was debate, vivid debate about that.

Some people say no, it's not acceptable to validate

a screening program only based on an open study.

An open study like ELCAP.

Even if it is published in a very good journal, we cannot accept that as

sufficient evidence to validate, really,

the screening from this new technology.

So what has been decided is in the USA but also in Europe.

Several programs have been set up to

validate the new device, the CT scan.

So, clinical trials.

So it has been randomized studies where half of the people were

assigned in an arm where they were just given chest X-rays and

in the other arm they were assigned to a CT scan.

So when they had a CT scan we followed-up them for a couple of years.

And when they had the standard chest X-ray they were also followed-up for

a couple of years.

And at the end of the day, we compare the survival.

Of course, also we compare if they had a tumor, if they have been extracted tumor,

if they are still smoker, if they have cessation of tobacco, and so on.

And what happens is the National Lung Cancer Study,

NLST, conducted by the NIH, National Institute of Health,

a public funded institute in the USA decided to conduct

this clinical trials in holding 50,000

smokers aged between 55 and 75.

And they were involved in this large randomized clinical trials and

followed for seven years.

And after seven years there was an early stop of this clinical trial.

Just because the people were enrolled in the,

how those CT Scan really had a better survival,

20% less mortality than in the control arm.

And also there was another old mortality which was much better

in the CT scan arm in comparison with the chest X-ray.

Meaning that, so this clinical trial, these very large clinical trials,

a sufficient amount of evidence was now on the table to say to the smokers.

Only, of course, to the heavy smokers, smokers who have smoked for

all their life, up to 50 or 55 or maybe 60 years old.

And now we can tell them, you can have this early screening for lung cancer.

And if we detect a tumor, if it is early enough,

we can detect a very small tumor and we can propose you surgery.

And early, we can tremendously improve your prognosis.

Of course, to say that has been hard to demonstrate, first.

Soon we always have to know that there is some counterpart,

some side effects of the early screening.

For instance, there is a lot of false positive.

Meaning that you may have an image which looks like an anomaly when,

in fact, it is nothing.

Just maybe something you had from the early beginning of your life.

But it is a image on the CT scan.

And we may, due to that, perform surgery.

And, of course, surgery of the thorax is not the same as surgery of the skin.

So it is very deep.

It is invasive and it is risky.

So when you go through these kind of procedures, you may be prone

to risk and you may have a side effect which sometimes may be very severe.

And we have to say that to the patient, of course.

But this is today probably something which is coming on the table.

Which is beginning to be reimbursed.

Which is recommended in the USA for sure.

We cannot expect anymore evidence even from the European studies

because they are too small, really, to demonstrate a 20% decrease in mortality.

Although it is very significant, it is, you need a lot of people to enroll

and it is very costly.

So it will probably not be performed for a long time now.

And we can say now that we have something which is not completely safe.

You may have some risk, to face some risk.

But which may be very interesting for

all the smokers who have smoked for all their life.

They have some solution, that they have to quit tobacco.

Because tobacco cessation is always beneficial for

the patient, even for reducing the risk of further lung cancer.

But also on all other disease associated with tobacco.

But if they cease, they stop that tobacco consumption, and

if they perform such screening program, they may be early detected for